1. Field of the Invention
The present invention relates to hearing aids, and in particular to a housing for a hearing aid having a shell with a component-containing housing received therein.
2. Related Application
Subject matter of the present application is related to the subject matter of copending U.S. application Ser. No. 807893, filed Dec. 11, 1985 (Nassler).
3. Description of the Prior Art
In hearing aid technology it is known to form a shell of moldable material to conform to the auditory canal of the hearing aid user sometimes referred to as an "ear mold". It is also known to insert a housing containing the electronic components of the hearing aid inside the shell. Such a hearing aid is known, for example, from Great Britain patent No. 2 070 890.
In hearing aids which are small enough so as to be substantially introduced into the auditory canal, facilitation of such insertion is aided as much by the structure of the hearing aid housing as by a space-saving arrangement of the integrated electronic components. As described in the aforementioned British patent, heretofore custom-made housings were formed for each patient, conforming to that patient's auditory canal, with the electronic components of the hearing aid then being built into the shell. This has the disadvantage, however, that a function test is only possible after the individual shell is ready and can be placed into the ear of the patient. The built-in components can be removed or dismantled for repair or replacement only by breaking open the housing, the housing usually being glued. Additionally, a canal for venting of the volume enclosed in the auditory canal by the device must be included during manufacture of the shell.
Such problems are also present in miniature hearing aids of the type, wherein the greater part of the housing is accomodated in the external ear, and only the receiver projecting from the hearing aid is introduced into the auditory canal. For devices having a relatively large cross-section at the outside surface thereof, one solution to the above problems is disclosed in German OS No. 14 87 272, wherein the individual elements of the hearing aid are accomodated in a housing which is inserted by means of a releasable latch into an intermediate housing. The exterior of the intermediate housing is adapted with the shell to the shape of the auditory canal of the user's ear.